Avalanche Forecast

Issued: Mar 20th, 2019 3:30PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Loose Wet and Persistent Slabs.

swerner, Avalanche Canada

South Coast.

Natural avalanche activity is possible especially on sun exposed slopes in the afternoon. Cornices are soft and weak. Avoid travel under, on or anywhere near cornices.

Summary

Confidence

Moderate -

Weather Forecast

Change in the weather pattern is coming. Starting with cloudy skies, falling temperatures and freezing levels by the weekend.THURSDAY: A mix of sun and cloud. Freezing levels 2600 m and treeline temperatures near +10 degrees. Ridgetop winds light from the South.FRIDAY: Cloudy. Freezing levels 2500 m and treeline temperatures near +3 degrees. Ridgetop winds moderate from the southeast.SATURDAY: Cloudy with light precipitation (5-15 mm) falling as rain at treeline and below treeline and snow in the alpine. Freezing levels 1600 m and treeline temperatures +2 degrees. Ridgetop winds light from the South.

Avalanche Summary

Natural loose wet avalanches up to size 1 were reported on Tuesday in the North Shore Mountains. Natural activity may start to taper off with cooler temperatures this weekend. Until then you can expect loose wet slides to continue.

Snowpack Summary

Snow surfaces are variable and the heat has likely eliminated any trace of cold snow except on high elevation north features. Melt-freeze conditions (more melt then freeze at lower elevations) exist on all other aspects and elevations and signs of snowballing, surface sluffing and loose wet avalanches are current.Deeper in the snowpack a layer of weak and sugary faceted grains sits on a melt-freeze crust about 50 to 120 cm deep. This layer is most prominent in the North Shore Mountains on north aspects. With little overnight re-freeze the warm temperatures will penetrate deeper and continue to destabilize the snowpack and possibly initiating larger persistent slab avalanches. Its hard to say how many hot days and warm nights it will it take to wake up the more deeply buried weak layers that we haven't thought about in a long time.

Problems

Loose Wet

Loose wet activity is expected to continue on all aspects and elevations except north facing, alpine slopes. Cornices are softening up and weak. You don't want to be under or near one of these looming monsters when they fail.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Cornices become weak with daytime heating or solar exposure.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

Aspects: North East, East, South East, South, South West, West, North West.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Persistent Slabs

Warm temperatures are penetrating deeper into the snowpack and a cohesive slab now sits above a weak layer. Its hard to say how long it will take for this warming to wake up the more deeply buried weak layers.

The likelihood of deep persistent slab avalanches will increase with each day of warm weather.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Valid until: Mar 21st, 2019 2:00PM